Let it not be said that psychological science doesn’t ask the big questions. You know — big questions, like: Which is better, a Snickers bar or a bag of chips? What does raising children have in common with a no-hitter in baseball? And, how valuable is a pair of Armani socks really?

And let it not be said that psychological science can’t provide sound answers. (They are, in order, “the Snickers bar,” “more than you’d think,” and “it depends.”)

The thing those big questions all have in common, of course, is the small matter of the secret of human happiness, the subject of this year’s “Bring the Family” Address at the APS 19th Annual Convention in Washington, DC.

APS Fellow and Charter Member Daniel Gilbert, director of the Hedonic Psychology Laboratory at Harvard University and author of last year’s bestseller, Stumbling on Happiness (2006, Knopf), managed not only to enlighten a packed audience of psychologists and their loved ones but also, with his great wit, made the crowd, well, happy.

Affective Forecasting
For most of human history, Gilbert said, happiness wasn’t much of a secret — everybody knew that happiness is just “what happens when you get what you want.” Getting what you wanted seldom happened back in the day, when people’s lives were nasty, brutish, and short. So people pretty much lived in a world of perpetual wanting. In modern society, our basic needs are much more easily attainable — yet, as Gilbert pointed out, we still live in a world of want.

What’s wrong? Gilbert, an expert in the study of affective forecasting — how people predict their emotional reactions to future events — says the problem has to do with how we aim at happiness. “We might not be aiming very well,” he said.

The science of aiming better at happiness goes back to the Enlightenment. In their correspondence, the French mathematicians Pierre de Fermat and Blaise Pascal wondered if happiness could be reduced to a formula that would cover every possible situation and help all humans improve their aim at the good life. The answer they came up with is this: The value of any action “is a function of the odds that it will get you where you want to be and the odds that you will like it.” The modern study of economic rationality has followed Fermat and Pascal’s basic insight, arriving at equations like the subjective expected utility decision rule: The subjective utility of an alternative equals its likelihood times its subjective value.

Multiplying the odds of an outcome by how much you’ll value it sounds like basic math, not rocket science. So economists scratch their heads when people don’t actually follow this easy formula in making decisions, and instead make choices that often lead them to further unhappiness. Why do people fail to act rationally when it comes to their happiness?

One would easily imagine that, of the two parts of Fermat and Pascal’s equation, it is the first — the odds you will get what you want part — that trips people up. But according to Gilbert, “what’s really hard, in gambling and in life, is to figure out how much you’re going to like it if you get exactly what you’re aiming for” — in other words, affective forecasting.

Comparison Shopping
One of the best ways to study how bad people are at doing such forecasting is to watch what makes them pull out their wallets. “Money is nothing more or less than a happiness storage device,” Gilbert explained. “It’s a great tool for finding out how much people think they’re going to value things in the future.”

He showed a slide of a DVD marked down to $14.99 from $19.99. You could almost sense the audience reaching for their back pockets. “These are the most magic words in marketing,” Gilbert said: “Price Cut.” When it seems like its price has changed in a favorable way, it raises the value of that DVD: “That change in price is a delight, and I’m gonna buy it.”

Economists say that what smart decision makers should do, before any purchase, is ask what else they can do with that same amount of money — in other words, compare with the possible. What psychologists like Gilbert have found, though, is that because it’s so hard to compare with the possible, we compare with the past instead. “This can get us in all sorts of trouble.”

Why do we compare with the past and not with the possible? “The human brain is, at every level, a change detector,” Gilbert explained. Change, not stable qualities, is what the senses are attuned to. Eyes don’t see objects, for instance, but changes in objects, so they constantly jiggle in order to keep the visual world in motion. Or take smell: That smelly guy on the subway doesn’t smell himself, Gilbert explained, because “three weeks ago he ripened to perfection; his smell isn’t changing so he can’t detect it.” It’s the same way when evaluating the value of things like DVDs or cars or jobs — the brain looks for comparisons.

One of the things that gets people in trouble with this approach is that our bases of comparison often shift.

Gilbert asked the audience to imagine the following scenario: On the way to the theater to see your favorite play, you have two $100 bills in your wallet, but you lose one of them on the way. The theater ticket costs $100. Would you spend your remaining bill on the theater ticket? Most people say they would.

But alter the terms slightly: You have already purchased your $100 ticket; you are on the way to the theater with just $100 in your pocket, as well as your ticket, but you lose the ticket. Would you then spend your remaining $100 on another ticket? Most people say they would not.

An economist would say that both situations are equivalent, and thus shouldn’t produce different actions. Yet people do feel differently about these two scenarios. In the second scenario, it feels like the price of the ticket has gone up — doubled. And just as people love to feel like they’re paying less for something than they might have, they hate to feel like they’re paying more for something than they should have.

Shifting comparisons leads to major errors when predicting how much we will like something when we get it, however.

You’ll Get Nothing, and You’ll Like It
Gilbert described a study done by himself, Carey Morwedge, Kristian Myrseth, and Tim Wilson, in which student participants sat down with a bag of potato chips and estimated how much they thought they’d like the snack. The participants then ate the chips and rated how much they actually did like them. It seems straightforward, but for a little detail: Some students made their judgments in a room that also contained other appetizing foods like a chocolate bar (“A Snicker’s bar is far and away the best thing you can put in your mouth without asking permission if you are under 22 years old,” Gilbert noted); other students performed the task in a room that contained less appetizing items like sardines and a can of Spam.

Although students were not told to consider the other items in the room, these implicit comparisons had a big effect on their predictions. Those in the “Spam room” predicted liking the chips much more than did those in the “chocolate room.” But crucially, the other foods present had no effect on participants’ judgment of the actual experience of eating the chips. “We use different rulers for experiencing and prediction,” Gilbert explained.

Shifting comparisons causes us to routinely “misimagine our futures,” Gilbert said. Which is why we shouldn’t let things like discounts factor into our decisions — whether it comes to DVDs or major purchases like cars. “Why is it irrational to compare the savings to the purchase price? Answer: Because it’s not what you’re going to be doing when you spend the money you saved…. When you’re spending the money, you’re not making the same comparison you made when thinking about whether you should save it.”

This is true, even when it comes to major life turnarounds. Gilbert cited a study comparing the happiness of paraplegics with that of lottery winners. One year after the accident or lottery win, respectively, the two groups were about equally happy. “When you imagine these things you’re comparing to your present state. But that’s not what you do when it becomes your present state.” For the same reason, things like career advancement (e.g., achieving tenure) actually have a negligible impact on happiness even if, beforehand, our happiness seems like it will completely hinge on them.

The Kids Aren’t Alright
So can psychological science provide any kind of roadmap for attaining happiness?

To answer this small question, Gilbert showed a slide of his mother, who had advised him that, to be happy in life, he should get married, earn a decent amount of money, and have children — a standard triumvirate when many people imagine what will make them contented.

Gilbert said that the science shows his mom to be only partially right (at this point, one could hear the anxious mooing of sacred cows being led to slaughter).

“What she was really right about was marriage,” Gilbert said. Studies have shown that people who are married are happier than people who are unmarried or cohabiting, suggesting there is a “marriage advantage” when it comes to life satisfaction. Mom’s second requirement, a good paycheck, is known to be much less important. Research shows that money has diminishing marginal utility: “Anybody who says money can’t buy happiness has never met someone who lives in a cardboard box under a bridge,” Gilbert said. “But anybody who tells you money buys happiness has never met a very very rich person.” Money makes a big difference when it moves you out of poverty and into the middle class, he explained, but it makes very little difference after that.

But the biggest blow science dealt to Gilbert’s mother, and received wisdom, is when it comes to kids. Children have a negative overall effect on happiness. “The more children you have, the less likely you are to say you are satisfied with your life,” Gilbert said. Studies that monitored how much satisfaction people got from their everyday activities showed that women were less happy when interacting with their children than when doing almost any other activity. The pleasure of being with their children was actually comparable to that of doing housework.

“Contrary to what the popular press tells us,” he said, “the most common symptom of empty-nest syndrome is smiling.”

Why, then, are children regarded as one of life’s greatest rewards? “We believe we get more pleasure from the things for which we pay the most,” Gilbert explained. A person who paid $30 for a pair of Armani socks thinks they are the best socks in the world and that his life would be incomplete without them, but he feels that way mainly because of how much he paid. The same is true of children. “When people sacrifice, when people hurt, when people pay, they come to value things more. … One of the conclusions we draw from how much we do for our children is that they must be tremendous sources of happiness.”

Gilbert — himself a father — likened raising children to a no-hitter in baseball, in which your favorite team finally hits a game-winning home run at the bottom of the ninth. The long, event-free innings are incredibly dull to endure, but the game will be remembered as a great experience afterward because of that one punctuating moment of delight. “That’s how memory works: One of its funny foibles is that it remembers things that are extraordinary or unusual.” This is the “illusion” that can cause parenthood to seem so rewarding when, after an exhausting day of tedium taking care of a child, the child finally beams up at you and says “I love you, Daddy.”

The Principle of Shifting Comparisons
Anticipating the protests of the mothers in the audience who would corner him after the talk and insist that their children are the best thing in their lives (it was the “Bring the Family Address,” after all), Gilbert again invoked the principle of shifting comparisons: Children are the best thing in a parent’s life, he agreed, “but only because they tend to get rid of every source of joy we had before they came along.”

When it comes to shooting for happiness, our intuitions, and the advice of well-meaning others (like Mom), often aim us the wrong way, and we end up shooting ourselves in our Armani-clad feet. This is nobody’s fault but the rapid pace of history. “This device [the brain] was created for an environment that it no longer knows how to navigate.”

Gilbert noted that psychological science has a unique role to play — namely, “telling us that our intuitions can be wrong,” and counseling discipline and rational thinking in its place. “If our species has any hope of walking sure-footedly into a future, it is going to be because we have begun to understand what makes us stumble.”